The invention relates to a communication method between N stations among which one is selected as a master station and becomes responsible for building and broadcasting at least one service information table such as the tables defined according to standards like MPEG or DVB, said master station communicating with the (N--1) other ones, called slave stations, according to a specific table management, and in a limited number of situations.
The standards MPEG and DVB have defined various service information tables describing the transport stream content. In MPEG case, these tables are referred to as PSI tables (Program Specific Information), while in DVB case, they are referred to as SI tables (Service Information). They provide the minimum information to enable an automatic configuration of the receiver to demultiplex and decode the various streams of programs within a multiplexed transport stream.
In an independent broadcast system, each station transmits independently its own tables, without taking care of what the other stations broadcast and without any communication between stations. Such an independent broadcast system is the simplest one, but possible only if some constraining conditions are fulfilled (e.g. the version number and section numbers have to be independent from station to station, section interleaving shall not be possible, . . . ), which is unfortunately not always the case.
In a central broadcast system as illustrated in FIG. 1 (that shows an emitting station 10 (ES) sending to a customer 12 (CM) a multiplexed stream MXS emitted by a multiplexor MUX 14 that receives several programs 1 to N), a station becomes responsible for building and broadcasting the tables for all the other stations, without communicating with them. The building and the transmission of these tables are relatively easy since the station 10 generating the transport stream knowns their content. Such a situation is however reserved to tables which are global (i.e. not service oriented) and for which no information is needed from the other stations.